1. Field of the Invention
The present invention relates to an input device for use with a computer system, and particularly to a keyboard and method for switching key code sets with a single modifier key.
2. Description of the Related Art
With ever increasing speed of the central processing unit (CPU), the capability of processing multimedia information such as audio and video data has become a required feature in current computer system configurations. Control of multimedia operations in prior art computer systems is largely obtained by switching between software applications through mouse operation. For instance, under the Windows operation system environment, it is typical to switch from one software application to another by selecting the required application with a series of mouse points-and-clicks. However, a series of complicated, and hence inconvenient, mouse movements, relocations and point-and-click actions will be required to browse through the video data in a DVD, listen to the music in an Audio CD, connect to a modem, or even make adjustments in the volume, quality and balance of sounds and so on.
Therefore, it has been proposed that a number of hot keys, such as CD, Video, Play, Fast Forward (FF), Fast Rewind (FR), Volume Up (Volume+), Volume Down (Volume-), Mute, Telephone, etc., be incorporated into the keyboard as an input device of the computer system to allow user interaction with the multimedia resources in the computer system through those hot keys. However, the implementation of those hot keys will require the consideration of factors such as increasing keyboard size, or retaining original keyboard size but decreasing hot key size. Any method is sure to increase cost by adding more wires and making new molds.
Another solution is accomplished with a multiple key combination method; for example, by first pressing and holding one of the Ctrl, Alt, and Shift keys and then striking another predetermined key such as a Function key of F1 to F12, so as to activate multimedia functions. Though without the drawback of increasing cost by adding more wires and making new molds as described in the hotkey method mentioned above, to activate a specific multimedia function with this method the user must simultaneously press with two fingers to preset combination keys and to memorize the representative functions of the key combinations. Such practice is therefore inconvenient to the user. Further, the selected key combinations might be used in some application software, thereby making the system function incomplete.